This project evaluated the efficacy of two doses of 4 different formulations of a growth hormone receptor antagonist currently under being examined for the treatment of acromegaly. Efficacy was determined by the ability of the drug to suppress serum concentrations of insulin-like growth factor (IGF)-I and IGF binding protein (IGFBP) -3. The results of this study provided significant new information for the advancing a successful treatment regimen in acromegalics. In addition, these studies provide new information for the development of an animal model of GH receptor deficiency that could be used to study growth and development. FUNDING Sensus Drug Development Corp. $35,200 07/01/98 - 6/30/99 PUBLICATIONS None P51RR00165-38 1/1/98 - 12/31/98 Yerkes Regional Primate Research Center